The Future of Building and 3D Printing in Space

The first 3D printer from Made In Space was installed aboard the International Space Station (ISS) in November 2014. The idea sounds cool, but many ordinary earthlings have yet to feel its impact.

The start-up, based at NASA Ames Research Center in California, has since installed a second 3D printer on the ISS. The Additive Manufacturing Facility (AMF) is the first commercial 3D printer in space. Brought to the ISS in 2016, the AMF is already printing orders for commercial customers, including the first 3D-printed advertisement in space, a crowdsourced sculpture and projects for educational programs, such as Enterprise In Space.

With the AMF, the implications are starting to become clear. 3D printing in space isn’t just meant to be a novelty, but a technology that enables humanity’s proliferation throughout the cosmos. Now, it’s possible for customers with a small wad of cash to 3D print plastic objects on the ISS, but, if Made In Space's plans pan out, we may see a future in which those customers can head to space themselves.

ENGINEERING.com spoke with Made In Space President Andrew Rush to learn about the company’s latest projects, including 3D printing a small satellite as well as organic matter in microgravity, developing a robot that can build satellites in space and a partnership dedicated to the first commercial space station. 

The AMF

The AMF platform uses fused deposition modeling (FDM) to melt thermoplastic filament and extrude it onto a substrate. The machine has been designed in such a way that it is remotely controlled by Made In Space from Earth and minimizes the amount of time that ISS residents need to interact with it, according to Rush.

The AMF is currently taking commercial orders aboard the ISS. Full specifications and order placement information are available here. (Image courtesy of Made In Space.)

“We designed the printer to be really, really easy to use because astronaut time is very precious and constrained,” Rush said. “We command the printer from the ground and manufacture the part, and then we tell the astronaut, the printer is done, so they kind of float over and pop the part out and utilize it. So, it really minimizes their time spent on the manufacturing process and maximizes the time they spend in utilization.”

Among the plastics that the AMF is able to print with is polyetherimide (PEI), also known by the brand name ULTEM. A temperature-resistant plastic with high mechanical strength, ULTEM has received a number of certifications that make it widely used in aerospace. However, printing with the material requires the ability to ensure stable, high temperatures within the print chamber while protecting the components of the printer. Despite these constraints, Rush says that the AMF will be printing the first parts in ULTEM on the ISS this month.

Rush also explained that the AMF was designed to be easily upgradable in order to expand its material set. “We intentionally designed the AMF to be very scalable, upgradable and really easy for the astronauts to use so that it’s a one-handed operation for the astronauts to swap out the printhead and install a new one, whether it be another single material FDM head, a syringe head, a multimaterial FDM head or a scanner,” Rush said. “The AMF that is on station today can do multimaterial printing. It’s plumbed for it and it’s designed for it. Honestly, we just need a customer to say they need to use those capabilities and then we would build and fly a multimaterial head and multimaterial canisters to support that activity.”

Despite some of the constraints of printing on the space station, 3D printing in space has advantages that aren’t seen on Earth. For instance, there’s no need for support structures. “[W]e can 3D print structures that cannot support their own weight,” Rush relayed. “We can make microgravity-optimized structures—such as gossamer structures that work really well in space—but would not be able to support their own weight if they were in gravity.”

From 3D Printing Electronics to Tissues in Microgravity

At the end of January 2017, Made In Space reported what may have been its most exciting parabolic flights to date. With experiments tightly secured, Made In Space rode an aircraft from the Flight Opportunities Program at Johnson Space Center in Houston, where a sharp nosedive succeeded by a sharp ascent allows for less than a minute of microgravity.

During the course of 200 such flights and about an hour total of microgravity, Made In Space was able to demonstrate a number of important firsts: digital light processing (DLP) 3D printing, metal casting, materials process, electronics 3D printing and bioprinting—all in microgravity. Each experiment revealed potential insights into the future of in-space manufacturing.

Made In Space equipment stowed aboard the parabolic flight aircraft. (Image courtesy of Made In Space.)

According to Rush, the experiments were meant to demonstrate the sheer range of manufacturing technology Made In Space hopes to bring to space. “Our approach is that we’re trying to bring manufacturing to space, not just FDM, not just metal welding, but every single manufacturing technique that is possibly useful in space or on other planets,” Rush said.

While FDM is useful for durable parts, it has its limitations. For instance, the minimum layer resolution on the AMF is 75 microns. FDM systems are also quite slow in comparison to other technologies. DLP 3D printing uses a projector to cure liquid photopolymer resin layer by layer, producing objects much more quickly with higher resolution.

Made In Space worked with DLP printer manufacturer B9Creations to successfully control the liquid resin while in microgravity. In addition to high resolution parts, it’s possible to create transparent parts with photopolymer 3D printing, possibly opening the door to creating optic components, such as lenses. “Resin printing is really interesting because there are materials that enable you to make ceramic parts,” Rush added. “From a space perspective, that means that, one day, you might be able to 3D print a heat shield, which is very important for spacecraft.”

Photopolymer 3D printing processes can also print with materials for lost wax casting. In this process, a part 3Dprinted from castable resin can be used as the basis for a mold. Once the mold is formed around the print, molten metal can be poured into the mold to create a metal part. During this most recent round of experiments, Made In Space demonstrated the ability to cast metal in microgravity using a proprietary process Made In Space refers to as Forced Metal Deposition (FMD), in which molten metal was cast into a 3D-printed mold to create metal objects.

An example metal-casted wrench manufactured by Made In Space. (Image courtesy of Made In Space.)

“Casting is super useful because it is a well-known process that people are very comfortable with,” Rush said. “No one objects to casting like they used to object to 3D printing. We’re comfortable with it from a manufacturing and verification perspective.”

The ability to fabricate with metal in space obviously opens up the possibility of producing more functional components in space, not just those that may be used to on Earth, but new parts that rely on materials harvested from asteroids and other bodies. For this reason, Made In Space also used the parabolic flights to experiment with material processing. The microgravity materials processor forced waste plastic through the system via forced convection and the use of a driven plate, which ground input material into smaller pieces.

A rendering of Made In Space's material recycler system, dubbed “R3DO.” (Image courtesy of Made In Space.)

“This is really important in the near term for recycling,” Rush said. “We want to recycle material on the station, take old parts or plastic bags or other material and turn it into 3D printer filament. We’re also looking further into the future at asteroid mining, for instance. There are several pieces to the pie of asteroid mining. First, you have to find the asteroid; then you have to get to the asteroid; then you have to dig material out of it and process the ore. So, we’re really laying the groundwork for those last two pieces.”

To get the most use out of these materials, Made In Space has been developing technology capable of fabricating fully functional objects. The Satellite Manufacturing Machine (SMM) is a combination 3D printer and robotic assembly system designed to, well, manufacture satellites. On the parabolic flights, Made In Space used the SMM to 3D print a picosatellite in microgravity.

The system first 3D printed a structural substrate before placing the necessary electronic components, such as a transmitter, battery, a solar panel and integrated circuits. Next, the printer laid down conductive traces, wiring the components together to create a functioning satellite capable of reproducing the functions of the original Sputnik, the first satellite launched into space. Upon completion, the picosat transmitted “Go Bucks,” a shout-out to Made In Space Chief Engineer Michael Snyder’s alma mater, Ohio State University.

“Half a century after Sputnik launched, we can robotically manufacture in microgravity. It can fit in the palm of your hand,” Rush said. “We did it completely robotically, completely autonomously. We pressed ‘go’ and it made this little chipsat that duplicated the behavior of Sputnik.”

Using a robotic pick-and-place system and the same 3D printing technology currently installed on the ISS, the SMM is designed to be versatile. While it can 3D print a Sputnik analog, it is also engineered to use just about any prefabricated components and 3D printing material needed to create other satellites as well. The idea is to be able to produce custom satellites on demand, beginning with small satellites such as the one made during parabolic flight and expanding from there.

“Now we’re making small satellites,” Rush said. “Soon we’re making cubesat-sized satellites, the size of bread loaves. Then, you can see how that technology progresses to factories on orbit that are manufacturing a wide variety of large, capable satellites.”

As if to push the boundaries of science fiction even further into science fact, Made In Space also experimented with bioprinting aboard the recent parabolic flights. A bioscaffold was 3D printed before living cells were distributed and attached using a 3D printer.

“There’s a lot of interesting research out there being done now on vascularized tissue, making it in a microgravity environment and bringing it back down to Earth. Ultimately, maybe being able to make heart valves, for example, and importing them back to Earth,” Rush explained. “Bioprinting may also be very integral to deep space missions, not only for food production, but, looking even further afield, for life support and environmental control systems, bio-based systems rather than mechanical systems. That’s the far-reaching future that we’re working toward.”

Building Space Stations

Before we can begin traversing the stars with biological life support systems, humanity may be able to extend its presence in low Earth orbit through the construction of a new space station. Axiom Space intends to do just that by constructing the world’s first commercial space station.

Ahead of the ISS’ retirement, Axiom plans to develop a module that would be installed on the space station in 2020. This will serve as the basis for constructing a complete station to succeed the ISS when it is ready to retire between 2024 and 2028. The goal may be a realistic one, given the experience of the Axiom team. 

A rendering of the Axiom Space station. The station will begin as a single module installed onto the ISS before subsequent modules and components are added. (Image courtesy of Axiom Space.)

The company is led by Michael Suffredini, who spent 10 years as NASA Space Station Program Office manager, where he was responsible for the creation, launch and operation of 460 metric tons of the ISS. If he did it before, he can likely do it again.

When Axiom’s first module—made up of sleeping quarters, restroom, galley, and experimentation and storage areas—does launch, Made In Space will be along for the ride. Because so much of what Made In Space does necessitates a microgravity environment, the company will have plenty of opportunities as a tenant of the Axiom module.

An obvious example is the use of an AMF facility on the module, but Rush explained that the company may also manufacture optical fibers from the Axiom Space station. To eliminate gravity-induced imperfections in ZBLAN optical fiber—used in medical products, fiber lasers and other near-infrared applications—Made In Space hopes to fabricate the material in space before returning it for use on Earth.

A picture of “Made In Space Fiber,” the device that will produce optic fibers aboard the ISS. (Image courtesy of Made In Space.)

Rush believes that Made In Space may even be able to aid in the manufacturing of the Axiom Space station with the use of its Archinaut system. Under a two-year, $20 million NASA contract, Made In Space, along with Northrop Grumman Corporation and Oceaneering Space Systems, aims to develop and deploy the Archinaut, a robotic assembly system capable of additively manufacturing parts that can be combined with prefabricated components, like reflectors, solar panels and sensors, to construct large-scale structures.

“The core manufacturing technology is extended structure additive manufacturing, which is basically a 3D printer with a small manufacturing size that can make things much larger than itself,” Rush said. “We’re not just talking about making trusses. We’re talking about eventually being able to make complex geometries and, with robotic manipulation, build large, bulk complex structures. As we progress, we want to be able to do multimaterial structures and integrate electric conduits so that there’s not a need for wiring harnesses.” 

A diagram of the Archinaut system assembling a satellite in space. (Image courtesy of Made In Space.)

Installed onto an external module on the ISS, the Archinaut would be able to create solar arrays, satellites and even space stations, according to Rush. “The ISS was built on the backs of astronauts in Extravehicular Mobility Units, taking prefabricated components that were launched from the ground and connecting those together,” Rush said. “It’s an amazing achievement, but, from a commercial perspective, we don’t have the money or the risk profile to support extravehicular activity assembly.” 

Rush claims that a small-scale prototype of the Archinaut’s base technology is already near completion and will be shipped to a commercial customer later this summer. Depending on the customer’s plans, this could be flown in the next year or two. The NASA-funded project is about three years from an on-orbit demonstration that will see Made In Space launch a small satellite and then assemble a large structure potentially over 10 meters in size.

After the technology has been proven for building satellites and solar arrays,it’s not difficult to imagine the Archinaut constructing portions of the Axiom Space station. At which point, Axiom Space will be able to take customers for its 60-day sovereign astronaut missions, shorter space tourism missions and more.

The Future of NewSpace

These endeavors combined take the costly burden off of Earth rockets to send supplies into space and may let humanity focus on living and working in space itself. The idea of space as something “out there” will become more and more distant, as we establish a thriving economy between Earth and those of us colonizing the stars.

Made In Space is already building up the commercial demand for space-based endeavors. With the first commercial 3D printer on the ISS, it’s become easier than ever for ordinary people to become a part of a world off-Terra. For instance, Enterprise In Space has launched the Print the Future competition, which will allow university and graduate students to 3D print a project on the ISS.

Rush concluded, “Our big goal, long-term vision as a company is to create the tools that will help people colonize space. This is a vision that is not unique to us. SpaceX has a similar vision of enabling exoplanetary travel, and they’re tackling that problem by building really cost-effective rockets that will serve as the wagon trains to the stars. We want to make the manufacturing technologies that will both help people live and work in space. The difference between going on a camping trip and settling are the tools you take with you. ”